More than 150 million Americans are under the highest-level extreme heat alerts during a wave of above-average temperatures.

A multiday heat wave is bringing high temperatures and health risks from the Midwest to the Northeast, prompting warnings and ...

High temperatures across the Plains, Midwest, Mid-Atlantic and Northeast are expected to hit at least 15 degrees above normal ...

Maps show where extreme humidity and 90- or 100-degree temperatures will affect about 255 million people across the United ...

Humidity will soon surge to extreme levels across 40 states. Find out where there will be excessive heat and humidity — and ...

Extreme humidity and heat will affect about 265 million people across the country this week. Maps show where and when to ...

The latest weather forecast shows a heat dome over the East Coast could send temperatures soaring in Massachusetts.

Tens of millions of people across the Midwest and East are enduring another sweltering day of dangerously hot temperatures as ...

A rare heat wave is set to bring triple ... for around 150 million people in 21 states. The extreme weather, which could last beyond the Fourth of July holiday weekend, has led to fires in the ...

The federal National Weather Service has issued heat warnings, advisories and watches urging people in parts of 30 states to "stay out of the sun" due to soaring temperatures this weekend.

Swaths of California sweltered Tuesday and things were only expected to get worse during the Fourth of July holiday week for parts of the United States with nearly 90 million people under heat alerts.

Excessive heat warnings are in place for much of the west coast and southern United States heading into the Fourth of July weekend, when millions of people will experience triple-digit ...